Gaseous ammonia production system and gaseous ammonia production method

Abstract

A gaseous ammonia production system (1) comprises: a heating unit (13) for heating liquid ammonia; and a first compressor (16) for compressing gaseous ammonia heated and vaporized by the heating unit (13), wherein at least some of the heat of the ammonia compressed by the first compressor (16) is supplied to the heating unit (13).

Description

Gaseous ammonia production system and gaseous ammonia production method

[0001] The present disclosure relates to a gaseous ammonia production system and a gaseous ammonia production method.

[0002] It is known that power can be obtained by burning ammonia as fuel in a combustor. Ammonia does not contain carbon in its molecules and does not produce carbon dioxide when burned. Therefore, including ammonia in the fuel can reduce carbon dioxide emissions into the atmosphere. Conventionally, when ammonia is used as fuel for devices such as gas turbines, it has been known to produce gaseous ammonia by vaporizing liquid ammonia.

[0003] Patent Document 1 discloses a fuel supply system including a vaporizer capable of heating and vaporizing liquid ammonia, and a gaseous ammonia line capable of introducing the gaseous ammonia vaporized in the vaporizer as fuel to a combustor of a gas turbine. The fuel supply system also includes a gaseous ammonia compressor provided in the gaseous ammonia line and capable of increasing the pressure of the gaseous ammonia flowing through the gaseous ammonia line.

[0004] International Publication No. 2022 / 172955

[0005] According to the fuel supply system described in Patent Document 1, the pressure of gaseous ammonia introduced into the combustor via the gaseous ammonia line can be easily adjusted to a target pressure. However, when the gaseous ammonia is pressurized, the temperature of the gaseous ammonia also increases. Therefore, the temperature of the ammonia pressurized by the gaseous ammonia compressor may be higher than the temperature required by the device that supplies the gaseous ammonia. However, when the temperature of the gaseous ammonia pressurized to meet the requirements of the device is cooled by a cooler, there is a risk of thermal energy loss.

[0006] Therefore, an object of the present disclosure is to provide a gaseous ammonia manufacturing system and a gaseous ammonia manufacturing method that are capable of suppressing loss of thermal energy.

[0007] A gaseous ammonia producing system according to the present disclosure produces gaseous ammonia. The gaseous ammonia producing system includes a heating unit that heats liquid ammonia and a first compressor that compresses the gaseous ammonia heated and vaporized by the heating unit. At least a portion of the heat of the ammonia compressed by the first compressor is supplied to the heating unit.

[0008] The heating unit may include a first heater that heats liquid ammonia with a first heat medium, and a second heater that heats the ammonia heated by the first heater with a second heat medium having a temperature higher than that of the first heat medium. The first compressor may compress gaseous ammonia heated and vaporized by the first heater and the second heater. At least a portion of the heat of the ammonia compressed by the first compressor may be supplied to the second heater.

[0009] The gaseous ammonia production system may include a cooler that cools the ammonia compressed by the first compressor, and a second compressor that compresses the ammonia compressed by the first compressor. At least a portion of the ammonia compressed by the first compressor may be supplied to the cooler.

[0010] In the cooler, the ammonia may be cooled by the third heat medium.The gaseous ammonia producing system may include a third heat medium flow rate adjuster that adjusts the flow rate of the third heat medium supplied to the cooler based on the temperature of the ammonia supplied to the second compressor.The gaseous ammonia producing system may include a gas flow rate adjuster that adjusts the flow rate of the gaseous ammonia produced by the gaseous ammonia producing system that is supplied to an ammonia supply destination.

[0011] The gaseous ammonia producing system may include a second heat medium flow rate adjuster that adjusts the flow rate of the second heat medium supplied to the second heater based on the temperature of the ammonia supplied to the first compressor.

[0012] The gaseous ammonia producing system may include a first heat medium flow rate adjuster that adjusts the flow rate of the first heat medium supplied to the first heater based on the temperature of the ammonia supplied to the second heater.

[0013] The gaseous ammonia producing system may include a gas-liquid separation unit that separates ammonia supplied from the heating unit into liquid ammonia and gaseous ammonia, supplies the separated liquid ammonia to the heating unit, and supplies the separated gaseous ammonia to the first compressor.

[0014] The gaseous ammonia producing system may include a cooler that cools the ammonia compressed by the first compressor, and a preheater that heats the ammonia supplied to the first heater or the second heater. In the cooler, the ammonia may be cooled by a third heat medium. The ammonia in the preheater may be heated by the third heat medium heated by heat exchange in the cooler.

[0015] A gaseous ammonia producing method according to the present disclosure is a gaseous ammonia producing method for producing gaseous ammonia. The gaseous ammonia producing method includes a step of heating liquid ammonia in a heating section, and a step of compressing the gaseous ammonia heated and vaporized by the heating section in a first compressor. At least a portion of the heat of the ammonia compressed in the first compressor is supplied to the heating section.

[0016] According to the present disclosure, it is possible to provide a gaseous ammonia manufacturing system and a gaseous ammonia manufacturing method that are capable of suppressing loss of thermal energy.

[0017] Fig. 1 is a schematic diagram showing a gaseous ammonia producing system according to a first embodiment. Fig. 2 is a schematic diagram showing a gaseous ammonia producing system according to a second embodiment. Fig. 3 is a schematic diagram showing a gaseous ammonia producing system according to a third embodiment. Fig. 4 is a schematic diagram showing a gaseous ammonia producing system according to a fourth embodiment. Fig. 5 is a schematic diagram showing a gaseous ammonia producing system according to a fifth embodiment. Fig. 6 is a schematic diagram showing a gaseous ammonia producing system according to a sixth embodiment.

[0018] Hereinafter, several exemplary embodiments will be described with reference to the drawings. Note that the dimensional proportions of the drawings are exaggerated for the convenience of explanation and may differ from the actual proportions.

[0019] First Embodiment First, a gaseous ammonia producing system 1 according to a first embodiment will be described with reference to Fig. 1. As shown in Fig. 1, the gaseous ammonia producing system 1 according to this embodiment includes an ammonia flow path LA, an ammonia tank 11, a pump 12, a heating unit 13, a first compressor 16, a cooler 17, and a second compressor 18. The ammonia flow path LA is provided with the ammonia tank 11, the pump 12, the heating unit 13, the first compressor 16, the cooler 17, and the second compressor 18 in this order. The gaseous ammonia producing system 1 produces liquid ammonia LNH ３ from gaseous ammonia GNH ３ The ammonia produced in the gaseous ammonia producing system 1 is supplied to an ammonia supply destination (not shown) via a gaseous ammonia supply port 19.

[0020] The ammonia tank 11 contains liquid ammonia LNH ３ Liquid ammonia (LNH) is stored. ３ may contain a small amount of water. ３ The ammonia tank 11 may be in a state where liquid ammonia and water are present, or may be in a state where liquid ammonia and ammonia water are present, respectively. The ammonia tank 11 and the pump 12 are connected via an ammonia flow path LA, and ammonia in the ammonia tank 11 is supplied to the pump 12 via the ammonia flow path LA.

[0021] The pump 12 pressurizes the liquid ammonia supplied from the ammonia tank 11. By pressurizing the liquid ammonia with the pump 12, it is possible to reduce the energy required for compression in a first compressor 16, which will be described later. The ammonia pressurized by the pump 12 may be, for example, 0.01 MPa or more and 1 MPa or less. The pump 12 and the first heater 14 are connected via an ammonia flow path LA, and the liquid ammonia pressurized by the pump 12 is supplied to the first heater 14 via the ammonia flow path LA. Note that, when the pressure of the liquid ammonia supplied from the ammonia tank 11 is high, the gaseous ammonia producing system 1 does not need to be equipped with the pump 12, and a pressure control valve or the like may be used instead of the pump 12.

[0022] The heating unit 13 heats the liquid ammonia using a heat medium. By heating the liquid ammonia with the heating unit 13, the liquid ammonia can be vaporized and gaseous ammonia can be generated from the liquid ammonia. The gaseous ammonia heated by the heating unit 13 may be, for example, at least 0.01 MPa but less than 1 MPa and at least 20°C but less than 100°C. The heating unit 13 may include two or more heaters. By heating the liquid ammonia using multiple heaters, the heaters can be made smaller as a whole. Furthermore, the liquid ammonia can be gradually heated using the multiple heaters, making it possible to easily control the vaporization state of the liquid ammonia. In this embodiment, the heating unit 13 includes a first heater 14 and a second heater 15.

[0023] The first heater 14 heats liquid ammonia with a first heat medium M1. Specifically, the first heater 14 heats liquid ammonia supplied from the ammonia tank 11 and pressurized by the pump 12. The first heater 14 then vaporizes at least a portion of the pressurized liquid ammonia. The first heater 14 is provided with a first heat medium flow path L1, and the first heat medium M1 passes through the first heat medium flow path L1. In the first heater 14, heat is exchanged between the liquid ammonia and the first heat medium M1, heating the liquid ammonia and cooling the first heat medium M1. The first heater 14 and the second heater 15 are connected via an ammonia flow path LA, and the ammonia heated in the first heater 14 is supplied to the second heater 15.

[0024] The first heat medium M1 is a fluid. The type of the first heat medium M1 is not particularly limited, and the first heat medium M1 may include at least one of a gas and a liquid. The liquid first heat medium M1 may include a liquid such as seawater, brackish water, fresh water, cooling water after equipment cooling, industrial water, or tap water, or a gas such as air. The gaseous first heat medium M1 may include air. From the viewpoint of cooling efficiency, the first heat medium M1 is preferably a liquid.

[0025] The second heater 15 heats the ammonia heated by the first heater 14 with a second heat medium M2 having a temperature higher than that of the first heat medium M1. The second heater 15 heats liquid ammonia contained in the ammonia supplied from the first heater 14 and can vaporize at least a portion of the liquid ammonia. The second heater 15 may also heat gaseous ammonia contained in the ammonia supplied from the first heater 14. The second heater 15 is provided with a second heat medium flow path L2, and the second heat medium M2 passes through the second heat medium flow path L2. In the second heater 15, heat is exchanged between the ammonia and the second heat medium M2, heating the ammonia and cooling the second heat medium M2. The second heater 15 and the first compressor 16 are connected via an ammonia flow path LA, and the ammonia vaporized in the second heater 15 is supplied to the first compressor 16.

[0026] The first compressor 16 compresses the gaseous ammonia heated and vaporized by the heating unit 13. Specifically, the first compressor 16 compresses the gaseous ammonia heated and vaporized by the first heater 14 and the second heater 15. The ammonia compressed by the first compressor 16 may be at least 1 MPa and less than 2 MPa. Furthermore, the ammonia compressed by the first compressor 16 may be at least 100°C and less than 250°C. The first compressor 16 and the cooler 17 are connected via an ammonia flow path LA. Furthermore, a first branch section B1 is provided between the first compressor 16 and the cooler 17 in the ammonia flow path LA, and a second heat medium flow path L2 is connected via the first branch section B1. Specifically, the second heat medium flow path L2 connects the first branch section B1 and the second heater 15.

[0027] A portion of the ammonia compressed by the first compressor 16 is supplied to the second heater 15 as the second heat medium M2. Here, the ammonia compressed by the first compressor 16 is heated by compression. Therefore, the ammonia compressed and heated by the first compressor 16 is supplied to the second heater 15 as the second heat medium M2, thereby being able to heat the ammonia heated by the first heater 14. On the other hand, of the ammonia compressed by the first compressor 16, a portion of the ammonia that was not supplied to the second heater 15 is supplied to the cooler 17.

[0028] The cooler 17 cools the ammonia compressed by the first compressor 16. Specifically, the cooler 17 cools the gaseous ammonia compressed by the first compressor 16 to generate gaseous ammonia having a higher pressure than the gaseous ammonia heated by the second heater 15 and a lower temperature than the ammonia compressed by the first compressor 16. The ammonia cooled by the cooler 17 may be at least 1 MPa and less than 2 MPa. Furthermore, the ammonia cooled by the cooler 17 may be at least 50°C and less than 150°C. The cooler 17 is provided with a third heat medium flow path L3, and a third heat medium M3 passes through the third heat medium flow path L3. Then, in the cooler 17, heat is exchanged between the heat of the ammonia compressed by the first compressor 16 and the heat of the third heat medium M3, thereby cooling the ammonia and heating the third heat medium M3. In this way, the ammonia is cooled by the third heat medium M3 in the cooler 17.

[0029] The third heat medium M3 is a fluid. The type of the third heat medium M3 is not particularly limited, and the third heat medium M3 may include at least one of a gas and a liquid. The liquid third heat medium M3 may include a liquid such as seawater, brackish water, fresh water, cooling water after equipment cooling, industrial water, or tap water, or a gas such as air. The gaseous third heat medium M3 may include air. From the viewpoint of cooling efficiency, the third heat medium M3 is preferably a liquid.

[0030] The cooler 17 and the second compressor 18 are connected via an ammonia flow path LA, and the ammonia cooled in the cooler 17 is supplied to the second compressor 18. A second branch section B2 is provided in the ammonia flow path LA between the cooler 17 and the second compressor 18, and a second heat medium flow path L2 is connected via the second branch section B2. The second heat medium flow path L2 connects the second heater 15 and the second branch section B2. The ammonia that has passed through the second heater 15 as the second heat medium M2 is supplied to the second compressor 18. The ammonia cooled in the cooler 17 and the ammonia that has passed through the second heater 15 as the second heat medium M2 are joined at the second branch section B2 and supplied to the second compressor 18.

[0031] The second compressor 18 compresses the ammonia compressed by the first compressor 16. In this embodiment, the second compressor 18 compresses the ammonia compressed by the first compressor 16 and cooled by the cooler 17. The second compressor 18 also compresses the ammonia compressed by the first compressor 16 and passed through the second heater 15 as the second heat medium M2. The second compressor 18 further compresses the ammonia compressed by the first compressor 16, and therefore can produce higher-pressure gaseous ammonia than when ammonia is compressed only by the first compressor 16. The ammonia compressed by the second compressor 18 may be at least 2 MPa and less than 6 MPa. The ammonia compressed by the second compressor 18 may be at least 100°C and less than 300°C.

[0032] The gaseous ammonia supply port 19 is provided in the ammonia flow path LA downstream of the second compressor 18. The gaseous ammonia supply port 19 is connected to an ammonia supply destination (not shown), and the gaseous ammonia compressed by the second compressor 18 is supplied to the ammonia supply destination via the gaseous ammonia supply port 19. The ammonia supply destination may be a combustor included in a combustion furnace such as a gas turbine, a boiler, a gas engine, or an industrial furnace, or a reactor such as a heat exchange reactor.

[0033] That is, it is possible to provide an ammonia utilization system including the gaseous ammonia producing system 1 and an ammonia supply destination that utilizes the gaseous ammonia produced in the gaseous ammonia producing system 1. For example, when the ammonia supply destination is a combustor, it is possible to provide a combustion system including the gaseous ammonia producing system 1 and a combustor that combusts the gaseous ammonia produced in the gaseous ammonia producing system 1. Furthermore, for example, when the ammonia supply destination is a reactor, it is possible to provide a reaction system including the gaseous ammonia producing system 1 and a reactor that generates a reaction product from a raw material that contains the gaseous ammonia produced in the gaseous ammonia producing system 1.

[0034] In the present embodiment, an example has been described in which a portion of the ammonia compressed by the first compressor 16 is supplied to the second heater 15 as the second heat medium M2, and a portion of the ammonia compressed by the first compressor 16 is supplied to the cooler 17. However, the ammonia compressed by the first compressor 16 may not be supplied to the cooler 17, and all of the ammonia compressed by the first compressor 16 may be supplied to the second heater 15 as the second heat medium M2. Therefore, at least a portion of the ammonia compressed by the first compressor 16 may be supplied to the heating unit 13 as a heat medium. Specifically, at least a portion of the ammonia compressed by the first compressor 16 may be supplied to the second heater 15 as the second heat medium M2. Therefore, the gaseous ammonia producing system 1 does not need to be provided with the cooler 17.

[0035] In the present embodiment, the gaseous ammonia supply port 19 is disposed in the ammonia flow path LA downstream of the second compressor 18. However, since the gaseous ammonia manufacturing system 1 does not need to include the cooler 17 and the second compressor 18, the gaseous ammonia supply port 19 may be disposed downstream of the second branch portion B2 or downstream of the second heater 15 in the second heat medium flow path L2.

[0036] Further, an example has been described in which a portion of the ammonia compressed by the first compressor 16 is directly supplied to the second heater 15 as the second heat medium M2. However, the heat of a portion of the ammonia compressed by the first compressor 16 may be supplied to the second heater 15 via an intermediate heat medium different from the second heat medium M2. For example, heat exchange may be performed between the heat of a portion of the ammonia compressed by the first compressor 16 and the heat of an intermediate heat medium different from the second heat medium M2, and the heat of the intermediate heat medium may be heat exchanged with the heat of the second heat medium M2. Then, the second heat medium M2 may be supplied to the second heater 15. With such a configuration, it is not necessary to directly supply ammonia to the second heater 15, and therefore it is not necessary to use an expensive material resistant to ammonia as a material for forming the second heater 15. Therefore, the heat of a portion of the ammonia compressed by the first compressor 16 may be supplied to the heating unit 13. Furthermore, the heat of at least a portion of the ammonia compressed by the first compressor 16 may be supplied to the heating unit 13. Specifically, at least a portion of the heat of the ammonia compressed by the first compressor 16 may be supplied to the second heater 15 .

[0037] Further, in the example described above, the second branch section B2 is provided between the cooler 17 and the second compressor 18 in the ammonia flow path LA, and the ammonia that has passed through the second heater 15 as the second heat medium M2 is supplied to the second compressor 18 without being cooled by the cooler 17. That is, a portion of the ammonia compressed by the first compressor 16 is supplied to the cooler 17. However, the second branch section B2 may be provided between the first branch section B1 and the cooler 17 in the ammonia flow path LA, and the ammonia that has passed through the second heater 15 as the second heat medium M2 may be supplied to the cooler 17. Therefore, at least a portion of the ammonia compressed by the first compressor 16 may be supplied to the cooler 17.

[0038] As described above, the gaseous ammonia producing system 1 according to this embodiment produces gaseous ammonia. The gaseous ammonia producing system 1 includes a heating unit 13 that heats liquid ammonia, and a first compressor 16 that compresses the gaseous ammonia heated and vaporized by the heating unit 13. At least a portion of the heat of the ammonia compressed by the first compressor 16 is supplied to the heating unit 13.

[0039] The gaseous ammonia producing method according to this embodiment is a gaseous ammonia producing method for producing gaseous ammonia. The gaseous ammonia producing method includes a step of heating liquid ammonia in a heating unit 13 and a step of compressing the gaseous ammonia heated and vaporized by the heating unit 13 in a first compressor 16. At least a part of the heat of the ammonia compressed in the first compressor 16 is supplied to the heating unit 13.

[0040] According to the gaseous ammonia producing system 1 and the gaseous ammonia producing method of the present embodiment, at least a part of the heat of the ammonia compressed in the first compressor 16 is supplied to the heating unit 13. Therefore, according to the gaseous ammonia producing system 1 and the gaseous ammonia producing method of the present embodiment, it is possible to suppress loss of thermal energy.

[0041] Furthermore, the heating unit 13 may include a first heater 14 that heats liquid ammonia with a first heat medium M1, and a second heater 15 that heats the ammonia heated by the first heater 14 with a second heat medium M2 that has a temperature higher than that of the first heat medium M1. The first compressor 16 may compress gaseous ammonia that has been heated and vaporized by the first heater 14 and the second heater 15. At least a portion of the heat of the ammonia compressed by the first compressor 16 may be supplied to the second heater 15.

[0042] With this configuration, the ammonia can be efficiently heated by the first heater 14 and the second heater 15. Therefore, the size of the heating unit 13 can be reduced. Also, the controllability of heating by the heating unit 13 can be improved.

[0043] The gaseous ammonia producing system 1 may also include a cooler 17 that cools the ammonia compressed by the first compressor 16, and a second compressor 18 that compresses the ammonia compressed by the first compressor 16. At least a portion of the ammonia compressed by the first compressor 16 may be supplied to the cooler 17.

[0044] With this configuration, it is possible to cool the ammonia that has been compressed and heated by the first compressor 16. Then, by further compressing the ammonia in the second compressor 18, it is possible to supply high-pressure gaseous ammonia at a temperature suitable for the ammonia supply destination.

[0045] Second Embodiment Next, a gaseous ammonia producing system 1 according to a second embodiment will be described with reference to Fig. 2. The gaseous ammonia producing system 1 according to this embodiment differs from the gaseous ammonia producing system 1 according to the first embodiment in that it includes a gas flow rate adjuster 23 and a third heat medium flow rate adjuster 20. Unless otherwise specified, the other points are the same as those of the gaseous ammonia producing system 1 according to the first embodiment, and therefore description thereof will be omitted.

[0046] The third heat medium flow rate adjustment unit 20 adjusts the flow rate of the third heat medium M3 supplied to the cooler 17 based on the temperature of the ammonia supplied to the second compressor 18. With this configuration, the temperature of the ammonia supplied to the second compressor 18 can be controlled within a predetermined range. Therefore, the temperature of the gaseous ammonia compressed by the second compressor 18 can also be controlled to be within a predetermined range. For example, the third heat medium flow rate adjustment unit 20 may adjust the flow rate of the third heat medium M3 supplied to the cooler 17 so that the temperature of the ammonia supplied to the second compressor 18 is equal to or higher than the dew point. The third heat medium flow rate adjustment unit 20 includes a first flow rate adjustment valve 21 and a first flow rate adjuster 22.

[0047] The first flow rate control valve 21 is provided in the third heat medium flow path L3 upstream of the cooler 17. The first flow rate control valve 21 adjusts the flow rate of the third heat medium M3 flowing through the third heat medium flow path L3, for example, by adjusting its aperture. The first flow rate control valve 22 is connected in the ammonia flow path LA between the cooler 17 and the second compressor 18. The first flow rate control valve 22 may control the first flow rate control valve 21 based on the temperature of the ammonia flowing from the cooler 17 to the second compressor 18 in the ammonia flow path LA, thereby adjusting the flow rate of the third heat medium M3 supplied to the cooler 17. The first flow rate control valve 22 may adjust the flow rate of the third heat medium M3 supplied to the cooler 17, for example, by controlling the aperture of the first flow rate control valve 21. The first flow rate control valve 22 includes a central processing unit (CPU), a random access memory (RAM), and a read-only memory (ROM). The CPU can read out a flow rate adjustment program stored in the ROM and execute flow rate adjustment.

[0048] The gas flow rate adjusting unit 23 adjusts the flow rate at which gaseous ammonia produced by the gaseous ammonia producing system 1 is supplied to the ammonia supply destination. With this configuration, an appropriate amount of gaseous ammonia can be supplied to the ammonia supply destination at a flow rate according to the load of the ammonia supply destination. The gas flow rate adjusting unit 23 includes a second flow rate adjustment valve 24 and a second flow rate adjuster 25.

[0049] The second flow rate control valve 24 is provided in the ammonia flow path LA between the second compressor 18 and the gaseous ammonia supply port 19. The second flow rate control valve 24 adjusts the flow rate of gaseous ammonia supplied from the gaseous ammonia supply port 19, for example, by adjusting its aperture. The second flow rate controller 25 is connected in the ammonia flow path LA between the second flow rate control valve 24 and the gaseous ammonia supply port 19. The second flow rate controller 25 may control the second flow rate control valve 24 based on the flow rate of gaseous ammonia flowing from the second flow rate control valve 24 to the gaseous ammonia supply port 19 in the ammonia flow path LA, thereby adjusting the flow rate of gaseous ammonia supplied to the ammonia supply destination. The second flow rate controller 25 may adjust the flow rate of gaseous ammonia supplied to the ammonia supply destination, for example, by controlling the aperture of the second flow rate control valve 24. The second flow rate controller 25 includes a CPU, RAM, and ROM, and the CPU can read a flow rate adjustment program or the like recorded in the ROM and execute flow rate adjustment.

[0050] As described above, in the gaseous ammonia producing system 1 according to the present embodiment, the ammonia may be cooled by the third heat medium M3 in the cooler 17. The gaseous ammonia producing system 1 may include a third heat medium flow rate adjuster 20 that adjusts the flow rate of the third heat medium M3 supplied to the cooler 17 based on the temperature of the ammonia supplied to the second compressor 18. The gaseous ammonia producing system 1 may include a gas flow rate adjuster 23 that adjusts the flow rate of the gaseous ammonia produced by the gaseous ammonia producing system 1 that is supplied to an ammonia supply destination.

[0051] According to the gaseous ammonia producing system 1 of this embodiment, an appropriate amount of gaseous ammonia can be supplied to the ammonia supply destination by the gas flow rate adjuster 23. On the other hand, if the ammonia flow rate flowing through the cooler 17 is varied by the gas flow rate adjuster 23, the temperature of the ammonia supplied to the ammonia supply destination may vary. However, according to the gaseous ammonia producing system 1 of this embodiment, the temperature of the gaseous ammonia produced by the gaseous ammonia producing system 1 can be adjusted by the third heat medium flow rate adjuster 20. Therefore, according to the gaseous ammonia producing system 1 of this embodiment, gaseous ammonia at a temperature and flow rate appropriate to the ammonia supply destination can be supplied to the ammonia supply destination.

[0052] [Third Embodiment] Next, a gaseous ammonia producing system 1 according to a third embodiment will be described with reference to Fig. 3. The gaseous ammonia producing system 1 according to this embodiment differs from the gaseous ammonia producing system 1 according to the second embodiment in that it is provided with a second heat medium flow rate adjuster 26. Unless otherwise specified, the other points are the same as those of the gaseous ammonia producing system 1 according to the second embodiment, and therefore description thereof will be omitted.

[0053] The second heat medium flow rate adjustment unit 26 adjusts the flow rate of the second heat medium M2 supplied to the second heater 15 based on the temperature of the ammonia supplied to the first compressor 16. For example, the second heat medium flow rate adjustment unit 26 may adjust the flow rate of the second heat medium M2 supplied to the second heater 15 so that the temperature of the ammonia supplied to the first compressor 16 is equal to or higher than the dew point. The second heat medium flow rate adjustment unit 26 includes a third flow rate adjustment valve 27 and a third flow rate adjuster 28.

[0054] The third flow rate control valve 27 is provided in the second heat medium flow path L2 upstream of the second heater 15. The third flow rate control valve 27 adjusts the flow rate of the second heat medium M2 flowing through the second heat medium flow path L2, for example, by adjusting its aperture. The third flow rate control valve 28 is connected in the ammonia flow path LA between the second heater 15 and the first compressor 16. The third flow rate control valve 28 may control the third flow rate control valve 27 based on the temperature of the ammonia flowing from the second heater 15 to the first compressor 16 in the ammonia flow path LA, thereby adjusting the flow rate of the second heat medium M2 supplied to the second heater 15. The third flow rate control valve 28 may adjust the flow rate of the second heat medium M2 supplied to the second heater 15, for example, by controlling the aperture of the third flow rate control valve 27. The third flow rate control valve 28 includes a CPU, RAM, and ROM, and the CPU can read a flow rate adjustment program or the like recorded in the ROM and execute flow rate adjustment.

[0055] As described above, the gaseous ammonia producing system 1 according to this embodiment includes the second heat medium flow rate adjusting unit 26 that adjusts the flow rate of the second heat medium M2 supplied to the second heater 15 based on the temperature of the ammonia supplied to the first compressor 16.

[0056] With this configuration, the temperature of the gaseous ammonia generated by the second heater 15 can be controlled within a predetermined range, and the temperature of the ammonia supplied from the second heater 15 can be maintained higher than the dew point. Therefore, the amount of liquid ammonia contained in the ammonia heated by the second heater 15 can be reduced, and the ammonia generated by the second heater 15 can also be completely vaporized. Therefore, it is possible to suppress the supply of liquid ammonia to the ammonia supply destination.

[0057] The gaseous ammonia producing system 1 according to this embodiment is equipped with a second heat medium flow rate adjuster 26 in addition to the gaseous ammonia producing system 1 according to the second embodiment. However, the second heat medium flow rate adjuster 26 may be provided in the gaseous ammonia producing system 1 according to the first embodiment.

[0058] [Fourth Embodiment] Next, a gaseous ammonia producing system 1 according to a fourth embodiment will be described with reference to Fig. 4. The gaseous ammonia producing system 1 according to this embodiment differs from the gaseous ammonia producing system 1 according to the third embodiment in that it is provided with a first heat medium flow rate adjuster 29. Unless otherwise specified, the other points are the same as those of the gaseous ammonia producing system 1 according to the third embodiment, and therefore description thereof will be omitted.

[0059] The first heat medium flow rate adjuster 29 adjusts the flow rate of the first heat medium M1 supplied to the first heater 14 based on the temperature of the ammonia supplied to the second heater 15. For example, the first heat medium flow rate adjuster 29 may adjust the flow rate of the first heat medium M1 supplied to the first heater 14 so that the temperature of the ammonia supplied to the second heater 15 exceeds the temperature of the liquid ammonia in the ammonia tank 11 and is lower than the temperature of the ammonia supplied to the first compressor 16. The first heat medium flow rate adjuster 29 includes a fourth flow rate adjustment valve 30 and a fourth flow rate adjuster 31.

[0060] The fourth flow rate control valve 30 is provided upstream of the first heater 14 in the first heat medium flow path L1. The fourth flow rate control valve 30 adjusts the flow rate of the first heat medium M1 flowing through the first heat medium flow path L1, for example, by adjusting its aperture. The fourth flow rate control valve 31 is connected in the ammonia flow path LA between the first heater 14 and the second heater 15. The fourth flow rate control valve 31 controls the fourth flow rate control valve 30 based on the temperature of the ammonia flowing from the first heater 14 to the second heater 15 in the ammonia flow path LA, thereby adjusting the flow rate of the first heat medium M1 supplied to the first heater 14. The fourth flow rate control valve 31 may adjust the flow rate of the first heat medium M1 supplied to the first heater 14, for example, by controlling the aperture of the fourth flow rate control valve 30. The fourth flow rate control valve 31 includes a CPU, RAM, and ROM, and the CPU can read a flow rate adjustment program or the like recorded in the ROM and execute flow rate adjustment.

[0061] As described above, the gaseous ammonia producing system 1 according to this embodiment includes the first heat medium flow rate adjusting unit 29 that adjusts the flow rate of the first heat medium M1 supplied to the first heater 14 based on the temperature of the ammonia supplied to the second heater 15.

[0062] With this configuration, the temperature of the ammonia generated by the first heater 14 can be controlled within a predetermined range, and ammonia at a stable temperature can be supplied to the second heater 15. Therefore, the temperature of the ammonia heated and generated by the second heater 15 can be maintained within a predetermined range. Therefore, the amount of liquid ammonia contained in the ammonia heated by the second heater 15 can be reduced, and the ammonia generated by the second heater 15 can also be completely vaporized. Therefore, it is possible to suppress the supply of liquid ammonia to the ammonia supply destination.

[0063] The gaseous ammonia producing system 1 according to this embodiment includes a first heat medium flow rate adjuster 29 in addition to the gaseous ammonia producing system 1 according to the third embodiment. However, the first heat medium flow rate adjuster 29 may be provided in the gaseous ammonia producing system 1 according to the first embodiment or the second embodiment.

[0064] Fifth Embodiment Next, a gaseous ammonia producing system 1 according to a fifth embodiment will be described with reference to Fig. 5. The gaseous ammonia producing system 1 according to this embodiment differs from the gaseous ammonia producing system 1 according to the fourth embodiment in that it includes a gas-liquid separation unit 32. Unless otherwise specified, the other points are the same as those of the gaseous ammonia producing system 1 according to the fourth embodiment, and therefore description thereof will be omitted.

[0065] The gas-liquid separation unit 32 separates the ammonia supplied from the second heater 15 into liquid ammonia and gaseous ammonia, supplies the separated liquid ammonia to the second heater 15, and supplies the separated gaseous ammonia to the first compressor 16. The gas-liquid separation unit 32 includes a gas-liquid separator 33 and a return flow path LR. The gas-liquid separator 33 is provided in the ammonia flow path LA between the second heater 15 and the first compressor 16. Specifically, the gas-liquid separator 33 is provided upstream of a point in the ammonia flow path LA where the third flow rate controller 28 is connected. The return flow path LR connects the gas-liquid separator 33 and the third branch portion B3. The third branch portion B3 is provided in the ammonia flow path LA between the first heater 14 and the second heater 15. Specifically, the third branch portion B3 is provided downstream of a point in the ammonia flow path LA where the fourth flow rate controller 31 is connected.

[0066] The gas-liquid separator 33 separates the ammonia heated by the second heater 15 into liquid ammonia and gaseous ammonia. The liquid ammonia separated by the gas-liquid separator 33 is returned to the upstream of the second heater 15 via a return flow path LR and supplied to the second heater 15. The gas-liquid separator 33 is also connected to the first compressor 16 via an ammonia flow path LA, and the gaseous ammonia separated by the gas-liquid separator 33 is supplied to the first compressor 16 through the ammonia flow path LA.

[0067] In the present embodiment, an example has been described in which the third branch portion B3 is provided between the first heater 14 and the second heater 15 in the ammonia flow path LA. However, the third branch portion B3 may be provided upstream of the first heater 14 in the ammonia flow path LA. The third branch portion B3 may be provided, for example, between the pump 12 and the first heater 14. The liquid ammonia separated in the gas-liquid separator 33 may be returned upstream of the first heater 14 via the return flow path LR and supplied to the first heater 14. That is, the liquid ammonia separated in the gas-liquid separator 33 may be supplied to the heating unit 13.

[0068] As described above, the gaseous ammonia producing system 1 according to the present embodiment may include the gas-liquid separation unit 32. The gas-liquid separation unit 32 may separate the ammonia supplied from the heating unit 13 into liquid ammonia and gaseous ammonia, supply the separated liquid ammonia to the heating unit 13, and supply the separated gaseous ammonia to the first compressor 16.

[0069] With this configuration, even if the ammonia is not completely vaporized in the heating unit 13, only the gaseous ammonia can be supplied to the first compressor 16. Furthermore, the liquid ammonia that has not been vaporized in the heating unit 13 can be reheated and vaporized in the heating unit 13. Therefore, according to the gaseous ammonia manufacturing system 1 according to this embodiment, it is possible to suppress the supply of liquid ammonia to the ammonia supply destination.

[0070] The gaseous ammonia producing system 1 according to this embodiment includes a gas-liquid separation unit 32 in addition to the gaseous ammonia producing system 1 according to the fourth embodiment. However, the gas-liquid separation unit 32 may be provided in the gaseous ammonia producing systems 1 according to the first to third embodiments.

[0071] [Sixth Embodiment] Next, a gaseous ammonia producing system 1 according to a sixth embodiment will be described with reference to Fig. 6. The gaseous ammonia producing system 1 according to this embodiment differs from the gaseous ammonia producing system 1 according to the fifth embodiment in that it includes a preheater 34. Unless otherwise specified, the other points are the same as those of the gaseous ammonia producing system 1 according to the fifth embodiment, and therefore description thereof will be omitted.

[0072] The preheater 34 heats the ammonia supplied to the first heater 14. With this configuration, the liquid ammonia can be gradually heated by the preheater 34, the first heater 14, and the second heater 15. The preheater 34 is provided in the ammonia flow path LA between the pump 12 and the first heater 14. The preheater 34 heats the liquid ammonia that is supplied from the ammonia tank 11 and pressurized by the pump 12.

[0073] The ammonia in the preheater 34 is heated by the third heat medium M3 heated by heat exchange in the cooler 17. Specifically, the preheater 34 is provided with a third heat medium flow path L3, and the third heat medium M3 passes through the third heat medium flow path L3. Then, in the preheater 34, heat exchange occurs between the heat of the ammonia and the heat of the third heat medium M3, so that the ammonia is heated and the third heat medium M3 is cooled. The preheater 34 and the first heater 14 are connected via an ammonia flow path LA, and the ammonia heated in the preheater 34 is supplied to the first heater 14.

[0074] In the present embodiment, an example has been described in which the preheater 34 is provided between the pump 12 and the first heater 14. However, the location of the preheater 34 may be changed depending on the temperature of the third heat medium M3 heated by heat exchange in the cooler 17. For example, the preheater 34 may be provided between the first heater 14 and the second heater 15. Then, the ammonia heated in the first heater 14 may be supplied to the preheater 34, and the ammonia heated in the preheater 34 may be supplied to the second heater 15.

[0075] As described above, the gaseous ammonia producing system 1 according to the present embodiment may include the cooler 17 that cools the ammonia compressed by the first compressor 16. The gaseous ammonia producing system 1 may include the preheater 34 that heats the ammonia to be supplied to the first heater 14 or the second heater 15. In the cooler 17, the ammonia may be cooled by the third heat medium M3. The ammonia in the preheater 34 may be heated by the third heat medium M3 that has been heated by heat exchange in the cooler 17.

[0076] The ammonia supplied to the first heater 14 or the second heater 15 is heated by the preheater 34, and therefore the ammonia can be heated efficiently. This allows the size of the heating unit 13 to be further reduced. In addition, the controllability of heating by the heating unit 13 can be further improved.

[0077] The gaseous ammonia producing system 1 according to this embodiment includes a preheater 34 in addition to the gaseous ammonia producing system 1 according to the fifth embodiment. However, the preheater 34 may be provided in the gaseous ammonia producing systems 1 according to the first to fourth embodiments.

[0078] The entire contents of Japanese Patent Application No. 2024-112359 (filing date: July 12, 2024) are incorporated herein by reference.

[0079] Although several embodiments have been described, the embodiments can be modified or varied based on the above disclosure. All components of the above embodiments and all features described in the claims may be individually extracted and combined, unless they contradict each other.

[0080] The present disclosure can contribute, for example, to Goal 7 of the United Nations-led Sustainable Development Goals (SDGs), "Ensure access to affordable, reliable and sustainable energy for all" and Goal 13, "Take urgent action to combat climate change and its impacts."

[0081] REFERENCE SIGNS LIST 1 Gaseous ammonia production system 13 Heating section 14 First heater 15 Second heater 16 First compressor 17 Cooler 18 Second compressor 20 Third heat medium flow rate adjusting section 23 Gas flow rate adjusting section 26 Second heat medium flow rate adjusting section 29 First heat medium flow rate adjusting section 32 Gas-liquid separation section 34 Preheater M1 First heat medium M2 Second heat medium M3 Third heat medium

Claims

1. A gaseous ammonia production system for producing gaseous ammonia, comprising: a heating unit that heats liquid ammonia; and a first compressor that compresses the gaseous ammonia heated and vaporized by the heating unit, wherein at least a portion of the heat of the ammonia compressed by the first compressor is supplied to the heating unit.

2. The gaseous ammonia manufacturing system according to claim 1, wherein the heating unit includes a first heater that heats liquid ammonia with a first heat medium, and a second heater that heats the ammonia heated by the first heater with a second heat medium having a temperature higher than that of the first heat medium, the first compressor compresses gaseous ammonia that has been heated and vaporized by the first heater and the second heater, and at least a portion of the heat of the ammonia compressed by the first compressor is supplied to the second heater.

3. The gaseous ammonia producing system according to claim 1 or 2, comprising: a cooler that cools the ammonia compressed by the first compressor; and a second compressor that compresses the ammonia compressed by the first compressor, wherein at least a portion of the ammonia compressed by the first compressor is supplied to the cooler.

4. The gaseous ammonia manufacturing system according to claim 3, wherein ammonia is cooled in the cooler by a third heat medium, and the gaseous ammonia manufacturing system comprises: a third heat medium flow rate adjusting unit that adjusts the flow rate of the third heat medium supplied to the cooler based on the temperature of the ammonia supplied to the second compressor; and a gas flow rate adjusting unit that adjusts the flow rate of the gaseous ammonia manufactured by the gaseous ammonia manufacturing system that is supplied to an ammonia supply destination.

5. The gaseous ammonia manufacturing system according to claim 2, further comprising a second heat medium flow rate adjusting unit that adjusts the flow rate of the second heat medium supplied to the second heater based on the temperature of the ammonia supplied to the first compressor.

6. The gaseous ammonia manufacturing system according to claim 2 or 5, further comprising a first heat medium flow rate adjusting unit that adjusts the flow rate of the first heat medium supplied to the first heater based on the temperature of ammonia supplied to the second heater.

7. The gaseous ammonia manufacturing system according to any one of claims 1 to 6, further comprising a gas-liquid separation unit that separates ammonia supplied from the heating unit into liquid ammonia and gaseous ammonia, supplies the separated liquid ammonia to the heating unit, and supplies the separated gaseous ammonia to the first compressor.

8. The gaseous ammonia manufacturing system according to any one of claims 2, 5 and 6, comprising: a cooler that cools the ammonia compressed by the first compressor; and a preheater that heats the ammonia to be supplied to the first heater or the second heater, wherein the ammonia is cooled in the cooler by a third heat medium, and the ammonia in the preheater is heated by the third heat medium that has been heated by heat exchange in the cooler.

9. A gaseous ammonia manufacturing method for manufacturing gaseous ammonia, the method comprising: heating liquid ammonia in a heating section; and compressing the gaseous ammonia heated and vaporized by the heating section in a first compressor, wherein at least a portion of the heat of the ammonia compressed in the first compressor is supplied to the heating section.

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